JPH058085A - Flux for soldering - Google Patents

Abstract

PURPOSE:To provide the flux for soldering having a good water washing property and excellent printability even when this flux is applied to solder cream. CONSTITUTION:This flux for soldering consists of at least one kind among a vinyl group-contg. compd., a carboxyl group-contg. compd. and an epoxy group-contg. compd. and a modified amine compd. obtd. by the reaction of an amine compd. having active hydrogen as a flux base resin.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flux used for soldering and the like.

[0002]

2. Description of the Related Art As a conventional soldering flux, CFC or the like is used as a cleaning solvent for cleaning residual flux after soldering.

However, in recent years, environmental damage caused by CFCs has become a big problem, and CFC countermeasures have become an important issue. Therefore, as one of the countermeasures against this CFC, it is considered that the residual flux is washed by washing with water.
Studies on water-soluble flux have been made in recent years.

As the water-soluble flux, there are used inorganic salt-based fluxes such as zinc chloride and hydrochloric acid, and organic salt-based fluxes such as amine hydrohalides and glycerin / polyethylene glycol.

However, these fluxes have too strong an activity of removing the oxide film on the metal surface, and when cleaning cannot be performed completely, they cause a problem of causing corrosion. When the flux No. 2 is applied to solder cream, there is a problem in that the viscosity is lacking and good printing cannot be performed, so a new water-soluble flux is desired.

[0006]

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a soldering flux which has good washing properties with water and has excellent printability even when applied to a solder cream.

[0007]

SUMMARY OF THE INVENTION The present invention provides a soldering flux using a modified amine compound as a base resin.

That is, the present invention uses a modified amine compound obtained by reacting at least one of a vinyl group-containing compound, a carboxyl group-containing compound and an epoxy group-containing compound with an amine compound having active hydrogen as a flux base resin. It consists of a soldering flux which is characterized by being used.

The amine compound having active hydrogen used for the modified amine compound in the present invention includes n-propylamine, n-hexylamine, ethylenediamine, trimethylenediamine, hexamethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, Examples include pentaethylenehexamine, monoethanolamine, diethanolamine, phenylenediamine, diaminodiphenylmethane and the like.

Examples of the vinyl group-containing compound used in the modified amine compound in the present invention include various (meth) acrylic acid esters, vinyl acetate, vinylpyrrolidone, styrene and (meth) acrylamide.

Examples of the carboxyl group-containing compound used in the modified amine compound in the present invention include acetic acid, benzoic acid, succinic acid, maleic acid, adipic acid, lactic acid, hydroxypivalic acid, dimethylolpropionic acid, citric acid, malic acid, Examples thereof include glyceric acid.

The epoxy group-containing compound used in the modified amine compound in the present invention includes methyl glycidyl ether / butyl glycidyl ether / phenyl glycidyl ether / glycidol / polyethylene glycol diglycidyl ether / neopentyl glycol glycidyl ether / trimethylolpropand glycidyl. Examples thereof include ether, glycerin polyglycidyl ether, sorbitol polyglycidyl ether, bisphenol type epoxy resin, novolac phenol type epoxy resin, versatic acid glycidyl ester, phthalic acid diglycidyl ester, and styrene oxide.

The modified amine compound used in the present invention is added to the epoxy group-containing compound by the addition reaction between the active hydrogen-containing amine compound and the vinyl group-containing compound and the condensation reaction with the carboxyl group-containing compound. It is easily synthesized by a reaction or a combination of these. This modified amine compound is a compound which itself has amine activity. In order to improve the water washability of this modified amine compound, 1
It is desirable to bond two or more hydrophilic groups such as hydroxyl groups in the molecule. Further, in order to improve printability when applied to cream solder, it is preferable to use a viscous material having a molecular weight of 200 or more. The modified amine compound may be modified together with modifications other than the above. In the soldering flux of the present invention, hydrohalic acids such as ethylamine, diethylamine, triethylamine, and aniline, which are generally used as activators, benzoic acid, succinic acid,
Organic acids such as maleic acid, adipic acid, lactic acid, hydroxypivalic acid, dimethylolpropionic acid, citric acid, malic acid and glyceric acid, and amines such as diphenylguanidine and triethanolamine can be used. As the solvent, alcohols such as isopropyl alcohol / butyl carbitol, esters such as ethyl acetate, hydrocarbons such as toluene, and ketones such as methyl ethyl ketone can be used. As the other additives, those generally used can be used.

Further, the ratio of the amine compound having active hydrogen to at least one of the vinyl group-containing compound, the carboxyl group-containing compound and the epoxy group-containing compound is 0.03 to 1.0 in terms of an equivalent ratio. Is preferred.

This is because when the equivalent ratio is less than 0.03, the amine cannot be sufficiently modified and the viscous property and water washability are insufficient. On the other hand, when it is larger than 1.0, there is no active hydrogen of the amine, and further reaction cannot be caused.

Further, it is preferable that the flux base resin of the present invention is contained in the soldering flux in an amount of 1 to 80% by weight. This is because when the modified amine compound is less than 1% by weight, the viscous property and water washability are insufficient, and
If it is more than 0% by weight, it becomes too viscous and it becomes difficult to prepare a flux.

[0017]

According to the present invention, since a modified amine compound that easily imparts water solubility and retains good water solubility even after heating by soldering is used as the base resin, it is possible to improve the water washability of the flux itself. it can. In addition, since the modified amine compound easily has a high molecular weight, it is possible to increase the viscosity. Therefore, even when the flux of the present invention is applied to, for example, cream solder, it has sufficient viscous properties, and good printability can be obtained.

[0018]

By adopting the flux of the present invention, it is possible to perform soldering which is excellent in water washability and is also excellent in printability when applied to a solder cream.

[0019]

[Examples] 215 g of triethylenetetramine, which is an amine compound having active hydrogen, was charged in a 1-necked four-necked flask equipped with a drainage tube, and the mixture was heated with stirring under a nitrogen atmosphere at 100 ° C.
The temperature was raised to. Next, 198 g of dimethylolpropynoic acid, which is a compound containing a carboxyl group, and 87 g of succinic acid are charged separately while paying attention to heat generation. While heating and removing the reaction water, the temperature is raised to 220 ° C. and maintained. After 3 hours, the acid value became 1 or less, so the reaction was terminated, the reaction mixture was cooled, and 298 g of butyl carbitol was charged and diluted. Thus, a modified amine solution which is a base resin of a viscous flux having a solid content of 60% was obtained.

55 g of the modified amine solution, 10 g of dimethylolpropionic acid, 15 g of S-40 (Nonionic surfactant manufactured by NOF CORPORATION), and 2 g of butyl carbitol were added.
A 0 g 4-necked flask was charged, heated and stirred at 140 ° C. and dissolved to prepare the flux of the first example.

After that, 10.0 wt% of this flux and 63Sn-37Pb as a solder powder were used, and the particle size was 45 to 63 μm.
By mixing the above with stirring, a solder cream was obtained. Then, the following test was performed on this solder cream.

As an evaluation of the printability, the rolling property and the rolling property when 50 sheets of the solder cream of the first embodiment were continuously printed on a glass epoxy substrate (150 × 160 × 1.6 mm) with a metal mask having a thickness of 0.2 mm were used. The bleeding property was observed.

As for the presence or absence of the solder balls, the solder cream of the first embodiment is applied to the QFP of 0.8 mm pitch and the thickness of 0.2 mm.
After printing with the metal mask of No. 2 and performing reflow (heating at 150 to 160 ° C. for 60 seconds as IR reflow, 20
The number of balls in 10 pads after heating (0 to 230 ° C. for 30 seconds) was observed.

As the water-cleaning property, the board soldered with the cream solder of the first embodiment was distilled with distilled water.
The state after being immersed in 0 ° C. warm water for 60 seconds and then immersed in room temperature water for 30 seconds and washed was visually observed with a microscope.

As the insulation resistance, a JIS2 type comb substrate is used to apply the solder cream of the first embodiment, and after the reflow, the test piece is washed with water. After that, this test piece was subjected to 10 V at 20 V in an atmosphere of 40 ° C. and 95% temperature.
After applying for 0 hours, 100 V was applied in the same atmosphere, and the insulation resistance was measured.

The results of the above tests are listed in Table 1. (Second Example) 333 g of butyl carbitol, which is a solvent, 181 g of triethylenetetramine, which is an amine compound having active hydrogen, and 0.5 g of hydroquinone, are charged into a 1 4-necked flask, and the mixture is heated under stirring in an air atmosphere to 100 ° C. did. While maintaining the temperature at 100 to 120 ° C. and paying attention to heat generation, 144 g of hydroxyethyl acrylate, which is a vinyl group-containing compound, was added dropwise over 1 hour, and subsequently, 176 g of acrylamide, which is a vinyl group containing compound, was added portionwise over 1 hour. The temperature was maintained at the same temperature for 5 hours to complete the reaction, followed by cooling. Thus, a modified amine solution which is a base resin of a viscous flux having a solid content of 60% was obtained.

Thereafter, 55 g of this modified amine solution, 10 g of dimethylolpropionic acid, 15 g of S-40 and 20 g of butyl carbitol were charged into a 4-necked flask.
The flux of the second embodiment was prepared by heating and stirring at 140 ° C. and melting.

After obtaining the cream solder of the second embodiment using the flux of the second embodiment in the same manner as in the first embodiment, the solderability of this cream solder will be described first.
The same test as in the example was conducted, and the results are shown in Table 1.

(Third Example) Butyl carbitol 3 which is an amine compound having active hydrogen in an 11-necked four-necked flask.
33 g of triethylenetetramine (198 g) was charged, and the mixture was heated with stirring under a nitrogen atmosphere to 100 ° C. 100-1
While maintaining the temperature at 20 ° C. and paying attention to heat generation, 302 g of glycidol, which is an epoxy group-containing compound, was added dropwise over 2 hours.
The temperature was maintained for 2 hours, the reaction was completed, and the mixture was cooled. Thus, a modified amine solution which is a base resin of a viscous flux having a solid content of 60% was obtained. 60 g of this modified amine solution
・ 10g of dimethylolpropionic acid ・ 15 of S-40
15 g of g-butyl carbitol was placed in a four-necked flask, heated and stirred at 140 ° C., and dissolved to prepare a flux of the third example.

After obtaining the cream solder of the third embodiment by using the flux of the third embodiment in the same manner as in the first embodiment, the solderability of this cream solder will be described as follows.
The same test as in the example was conducted, and the results are shown in Table 1.

(Fourth Example) 333 g of butyl carbitol which is a solvent and 34 g of monoethanolamine and 118 g of diethanolamine which are amine compounds having active hydrogen are charged into a 11-necked four-necked flask and heated to 100 ° C. with stirring under a nitrogen atmosphere. Warmed. While maintaining the temperature at 100 to 120 ° C. and paying attention to heat generation, 348 g of glycerin diglycidyl ether containing an epoxy group was added dropwise over 2 hours. The temperature was maintained for 3 hours, the reaction was completed, and the mixture was cooled. Thus, a modified amine solution which is a base resin of a viscous flux having a solid content of 60% was obtained.

55 g of this modified amine solution, 10 g of dimethylolpropionic acid, 15 g of S-40, and 20 g of butyl carbitol were charged into a four-necked flask, and 140
The flux of the fourth embodiment was produced by heating and stirring at 0 ° C. and melting.

After obtaining the cream solder of the fourth embodiment using the flux of the fourth embodiment in the same manner as in the first embodiment, the solderability of the cream solder will be described as follows.
The same test as in the example was conducted, and the results are shown in Table 1.

(First Comparative Example) Instead of the modified amine, triethylenetetramine used as a raw material of the modified amine was used. 75 g of triethylenetetramine, 10 g of dimethylolpropionic acid, and 15 g of S-40 were charged into a four-necked flask and heated to 140 ° C. with stirring to dissolve the mixture.
The flux of the comparative example was produced.

The flux of the first comparative example was obtained in the same manner as in the first example to obtain the cream solder of the first comparative example.
The same test as in the example was conducted, and the results are shown in Table 1.

(Second Comparative Example) Polyethylene glycol # 600 was used in place of the modified amine. 75 g of polyethylene glycol # 600, 10 g of dimethylolpropionic acid, and 15 g of S-40 were charged in a four-necked flask, and heated and stirred at 140 ° C. to dissolve to prepare a flux of the second comparative example.

The flux of the second comparative example was obtained in the same manner as in the first example to obtain the cream solder of the second comparative example.
The same test as in the example was conducted, and the results are shown in Table 1.

[0038]

[Table 1]

As described above, when the flux containing the modified amine compound of the present invention as the base resin is used, good printability and washability can be exhibited, and the use of CFCs or the like which cause environmental damage is not required. It enables highly reliable soldering.

In the above embodiment, the solder cream was obtained from the base resin of the flux of the present invention. However, the base resin of the present invention can be applied to other solders other than the solder cream. It can also be applied to post flux.

The flux of the present invention can be applied to various cleaning agents other than water cleaning by selecting the composition of the modified amine compound.

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Masami Aihara             4 No. 671 Mizusui, Noguchi Town, Kakogawa City, Hyogo Prefecture             Harima Kasei Co., Ltd.

Claims (3)

[Claims] 1. A flux base resin comprising a modified amine compound obtained by reacting at least one of a vinyl group-containing compound, a carboxyl group-containing compound and an epoxy group-containing compound with an amine compound having active hydrogen. Flux for soldering. 2. The ratio of the amine compound having active hydrogen to at least one of the vinyl group-containing compound, the carboxyl group-containing compound and the epoxy group-containing compound is 0.03 to 1.0 in terms of an equivalent ratio. The flux for soldering according to claim 1, wherein the modified amine compound obtained by the reaction in (1) is used as a flux base resin. 3. The soldering flux according to claim 1, wherein the flux base resin contains 1 to 80% by weight.